Where does triple fusion take place in a flowering plant? Why is it so called? Mention its significance.

Explanation

Triple fusion : It is a fertilisation that involves fusion of one male gamete and two polar nuclei ( or secondary nucleus, if the two have already fused) in the central cell of embryo sac.
It takes place in the central cell of an embryo sac. Three nuclei are involved in triple fusion, i.e., one male nucleus and two polar nuclei in the central cell therefore, the process is termed triple fusion.
Significance: Endosperm is triploid and helps in providing nourishrment to the embryo